A thin two-way ratchet wrench, where the thickness of a working part (10) thereof is less than or equal to 30 mm, suitable for working in confined spaces, implementing two work modes, and allowing stable and convenient switching between the two work modes. When using the thin two-way ratchet wrench, an input torque inputted by a user is alternately a clockwise torque or a counterclockwise torque, while an output torque at an output extremity (101) of the thin two-way ratchet wrench is either a clockwise torque or a counterclockwise torque.